Researchers have introduced a new photonic system designed to overcome that limitation. The scientists, from the University of Pennsylvania and Montana State University, combined the 2D semiconductor molybdenum diselenide (MoSe₂) with a photonic crystal nanocavity for the device, enabling light signals to be controlled by light while consuming extremely low energy.
Photonic devices, which process information using light rather than electricity, have long been viewed as a promising path toward faster, more energy-efficient computing systems.
However, one major challenge has limited their development: photons, or particles of light, do not naturally interact with one another easily.
Building a light-based computing platform “Our primary motivation was to advance the field of all-optical computing—a long-standing dream of building systems that process information using light instead of electricity,” Li He, assistant professor at Montana State University and senior author of the paper, as reported by Tech Xplore.
“Because light travels faster and generates less heat than moving electrons, these systems could be significantly more powerful and energy-efficient than today’s electronic chips. However, to make this a reality, we faced a fundamental challenge: photons (i.e., light particles) typically do not interact with one another,” he continued.
To solve this issue, according to the findings published in Physical Review Letters, the researchers focused on creating stronger interactions between photons using exciton-polaritons, hybrid quasiparticles formed when photons strongly couple with excitons inside semiconductors.
They used a single layer of MoSe₂ and integrated it with a silicon nitride nanobeam cavity engineered to tightly confine light. Achieving ultra-low energy optical switching.
The confined nanocavity helped amplify interactions between light and matter within the device, enabling ultrafast optical switching at very low power levels.
“By forcing light to couple strongly with the matter in atom-thin MoSe₂ layers, we can effectively have photons interact and change the system’s behavior using very little optical energy. “We achieved this by creating a hybrid state known as an exciton-polariton.
